"I think what our job now in Congress is to ... accept responsibility for issues of war," he said. "I hope Congress and the Senate next week votes to get the United States out of aiding Saudi Arabia in this very terrible war."

Murphy separately told reporters that he believes the resolution will likely be brought up for a vote next week.

The Senate also wants to tackle a bill to combat online sex trafficking and a mammoth government funding bill.

Murphy, Sanders and Lee introduced their resolution late last month, arguing the U.S. military's involvement is unconstitutional because Congress has not had a say in entering the conflict.

Under a provision of the International Security and Arms Export Control Act of 1976, they can get a vote on the Senate floor within 10 days of its introduction. It is subject to up to 10 hours of debate.

The resolution calls for any U.S. forces not involved in fighting al Qaeda or related groups to be out of the country within 30 days.

Yemen is locked in a years-long civil war after Houthi rebels took over the capital and President Abed Rabbo Mansour Hadi fled to the southern city of Aden.

Saudi Arabia formed a coalition and intervened in support of Hadi. In response, the U.S. has provided support for the Saudi campaign.

But some members of Congress have been critical of its impact on civilians and the resulting humanitarian crisis.

The Senate held a closed-door, all-members briefing on Yemen, which appeared to grow contentious.

Murphy called the briefing a "blatant effort to ignore reality."

"That is the most frustrating briefing I have been in since I have been a member of Congress. That wasn't a briefing, it was spin," he said.

He added "that's the most angry I've been at a briefing in all my time here" and that he told the administration officials during the meeting that he thought "they were misleading the Senate."